1st Generation of Cybermats: The Cybermats first featured in The Tomb of the Cybermen. The original Cybermats had crystalline eyes and a segmented body with sensors along their base.
2nd Generation of Cybermats: The Cybermats that appeared in The Wheel in Space were very similar to the ones that had appeared in The Tomb of the Cybermen. They had stronger armour and solid photoreceptors for eyes.
3rd Generation of Cybermats: The 3rd generation of Cybermats were a lot larger than the previous versions, they still had a segmented body but no eyes. The Cybermat that appeared in Revenge of the Cybermen could be remote controlled.
4th Generation of Cybermats: The Cybermat that featured in Closing Time is similar in design to the 1960’s versions. This Cybermat may appear cute and harmless but beware of its bite! This is the first Cybermat to have teeth and like the Cybermen it had ‘teardrop’ eyes. The Doctor said that it had a brain, it is not known what life form the brain and teeth were extracted from.
Cybermites: Cybermites are upgraded Cybermats, they’re far more flexible and advanced. They usually travel around in groups and have the capabilities to upgrade humans.
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